Cutting device



F. W. DAVIS CUTTING DEVICE Sept. 8, 1936.

Filed Feb. 3, 1956 2 Sheets-Sheet l 5' Inugnlor Z arresZ Eva's By'ag I W4 6 Aifomey Sept. 8, F w vjs CUTTING DEVICE Filed Feb. 5, 1936 2 Sheets-Sheet 2 0 i v I /7 7 l A5 I r lnvenlor z orresf Patented Sept. 8, 1936 UNITED STATES 2,053,702 CUTTING DEVICE Forrest W. Davis, Elkins, W. Va.

Application February 3 Claims.

The present invention relates to new and use ful improvements in cutting devices for use particularly by firemen but it will be understood, of course, that a device in accordance with the present invention may be used for any purpose for which it may be found adapted and desirable.

The primary object of the invention is to provide, in a manner hereinafter set forth, a power driven machine embodying a novel construction, combination and arrangement of parts through the medium of which holes for the reception of a hose or nozzle may be expeditiously cut in floors, walls or partitions and other places.

Another very important object of the invention is to provide a device of the aforementioned character embodying novel cutting means.

still another very important object of the invention is to provide, in a cutting device of the character described, a novel arrangement of motor for driving the device, shield for protecting the hands of the operator and facilitating the handling of the device, said shield enclosing the motor, etc.

Other objects of the invention are to provide a hole cutting device of the character set forth which will be comparatively simple in construction, strong, durable, highly eflicient and reliable in use, compact, light in weight, and which may be manufactured at a low cost.

All of the foregoing and still further objects and advantages of the invention will become apparent from a study of the following specification, taken in connection with the accompanying drawings wherein like characters of reference designate corresponding parts throughout the several views, and wherein:

Figure 1 is a view in front elevation of a hole cutting device constructed in accordance with the present invention.

Figure 2 is a view in vertical section through the invention.

Figure 3 is a bottom plan view of the cutting head.

Figure 4 is a top plan view of the cutting head.

Figure 5 is a fragmentary view, showing the arrangement of the bits and supporting arms constituting parts of the cutting head.

Referring now to the drawings, in detail, it willbe seen that the embodiment of the invention which has been illustrated comprises a substantially frusto conical shield l of suitable dimensions and material, the small end of said shield being lowermost and closed, as at 2. The upper end of the shield I is open, as best seen in Figure 2 of the drawings. Mounted centrally in 3, 1936, Serial No. 62,208

the lower portion of the shield I is a vertical electric motor 3 which is rigidly secured in position by brackets 4.

A shaft 5 depends from the electric motor 3 and is journaled in a bearing 6 which is provided therefor in the bottom 2 of the shield I. Mounted in the upper portion of the shield I on diametrically opposite sides thereof are handles '1. Adjacent one of the handles 1 is an electric switch 8 which controls the motor 3.

Detachably mounted on the lower end portion of the shaft 5 is a cutter head which is designated generally by the reference numeral 9. The head 9 includes a chuck I0 which is removably secured to the shaft 5 by a set screw H. Projecting from the chuck I0 are outwardly and downwardly curved arms 12 on the lower end portions of which annular inner and outer saws l3 and [4, respectively, are rigidly secured, as at [5. As illustrated to advantage in Figure 2 of the drawings, the free end portions of the arms H. are engaged between the saws l3 and I4 in a manner to space said saws concentrically with respect to each other.

Rigidly mounted between the inner and outer annular saws l3 and M are spiral bits IS the blades ll of which are spaced above the teeth l8 on the lower ends of said saws l3 and I4. Referring now to Figure 5 of the drawings, it will be seen that the upper ends of the bits [6 are disposed adjacent the forward sides of the arms l2 as the heads 9 rotate to assure the free discharge of the cuttings. The reference nu meral l9 designates an auger which is removably secured in the lower end portion of the chuck 9 by a set screw 20. The auger [9 extends centrally through the inner saw l3 and below the lower end thereof.

Briefly, the operation of the device is substantially as follows:

The electric motor 3 is energized through the medium of thG'QOIItIOI switch 8 and the operator, gripping the handles 1, engages the auger I! with and drives said auger into the work, such as a floor, wall or the like in which it is desired to cut a hole for the reception of a fire hose or nozzle. After the auger l9 has entered the material, the annular saws l3 and I4 engage the material and begin to function. The cuttings between the spaced inner and outer annular saws l3 and M are removed and discharged by the substantially spiral bits l6 at the upper ends of said saws l3 and M. It will thus be seen that a circular hole of suflicient diameter may be expeditiously cut. The lower portion of the shield l is provided with a plurality of ventilating openings 2! for the electric motor 3. In addition to rigidly supporting and enclosing the electric motor 3, the shield I protects the hands and arms of the operator against injury from chips, etc., which may be thrown from the rapidly rotating head 9.

It is believed that the many advantages of a cutting device constructed in accordance with the present invention will be readily understood, and although a preferred embodiment of the machine is as illustrated and described, it is to be understood that changes in the details of construction and in the combination and arrangement of parts may be resorted to which will fall within the scope of the invention as claimed."

What is claimed is:

1. A cutting device comprising spaced inner and outer annular saws, substantially spiral bits mounted between said saws, and means for rotating the saws.

2. A cutting device of the class described comprising a drive shaft, and a cutting head mounted on said drive shaft, said cutting head including a chuck removably mounted on the drive shaft, arcuate arms projecting from the chuck, spaced inner and outer annular saws rigidly mounted on the free end portions of the arms, substantially spiral bits mounted between said saws, and an auger mounted in the chuck and projecting centrally through and beyond the saws.

3. A cutting device of the class described comprising a substantially frusto conical shield, said shield being closed at one end, an electric motor mounted in the shield, a shaft driven by the motor and extending rotatably through the closed end of the shield, handles mounted in the shield, and a cutting head mounted on the shaft.

FORREST W. DAVIS. 

